Christmas Day dawned clear and mild, a green Christmas if ever there was one. And yet, in spite of the absence of such traditional accompaniments as snow and ice, the spirit of the season was there in abundance. Ned and Laurie, wakening early to the sound of church bells, felt Christmasy right from the first conscious moment. When they hastened down the hall for their baths, they could hear George and Hal Goring on the floor below uniting in what they fondly believed was song. Later, at breakfast, beside a perfectly wonderful repast in which chicken and little crisp sausages and hot, crisp waffles played leading rÔles, the Doctor and Miss Tabitha had placed at each plate a Christmas card tied by a tiny blue ribbon to a diminutive painter’s brush! Later on there was to be a tree in the Doctor’s living-room. In fact, the tree was already there, and the boys had spent much of the preceding evening trimming it and placing around its base inexpensive gifts of a joking nature for one another and the Doctor and Miss Tabitha and the two instructors who were there.

Laurie and Ned had exchanged presents with each other and had received several from home, not the least welcome of which was a check from their father. And they had bought small gifts for George and Bob. Also, though you needn’t tell it around school, Laurie had purchased a most odoriferous and ornate bottle of perfume for Polly! So when, shortly after breakfast, Ned suggested that Laurie take Bob’s present over to him, Laurie evinced entire willingness to perform the errand. That he carried not one gift but two in his pockets was, however, beyond Ned’s knowledge. A cheerful whistling from the back of the house drew Laurie past the front entrance, and he found Bob, attired in any but festal garments, swinging open the bulkhead doors. A pair of old gray trousers and a disreputable brown sweater formed most of his costume. At sight of Laurie he gave a joyful whoop.

“Merry Christmas!” he called. “I was going over to see you in a minute. Thomas is in bed with a cold or something, and I’m furnace-man and general factotle—”

“Factotum, you mean,” laughed Laurie.

“All right! As you fellows say, what do I care? I don’t own it. Now you’re here, you can just give me a hand with this load of junk. Dad says it doesn’t look shipshape for Christmas.” Bob indicated more than a dozen paint-cans, empty, partly empty, or unopened, and a mess of brushes, paddles, and rags that they had set there last evening. “I suppose a lot of these might as well be thrown away, but we’ll dump the whole caboodle down in the cellar for now.”

“All right,” agreed Laurie. “First, though, here’s something that Ned and I thought you might like. It isn’t anything much, you know, Bob; just a—a trinket.”

“For me?” Bob took the little packet, and removed the paper and then the lid, disclosing a pair of silver cuff-links lying in a nest of cotton-wool. As Laurie said, they weren’t much, but they were neat and the jeweler had made a very good job of the three plain block letters, R. D. S., that he had engraved on them. “Gee, they’re corking!” exclaimed Bob, with unmistakable sincerity. “I needed them, too, Nod. I lost one of a pair just the other day, and—”

“I know you did. That’s why we got those.”

“Well, I’m awfully much obliged. They’re great. I’ve got a couple of little things upstairs for you chaps. They aren’t nearly so nice as these, but I’ll get ’em—”

“Wait till we finish this job,” said Laurie. “Grab a handful and come on. Is Thomas very sick?”

“I guess not,” replied Bob, as he followed the other down the steps. “He ate some breakfast, but aunt thought he’d better stay in bed. I had a great time with the furnace this morning. Got up at half-past six and shoveled coal to beat the band!”

“Where do you want to put these?” asked Laurie.

“Anywhere, I guess. Hold on; let’s dump ’em on the shelves in the closet there. Then they’ll be out of the way. Some day we’ll clean the cans all out, and maybe we’ll get enough to paint that arbor we’re going to build. Here you are.”

Bob led the way to a small room built against the rear wall of the big cellar. Designed for a preserve closet, its shelves had probably long been empty of aught save dust, and the door, wide open, hung from one hinge. It was some six feet broad and perhaps five feet deep, built of matched boards. Before Bob entered the cobwebby doorway with his load of cans, its only contents were an accumulation of empty preserve-jars in a wooden box set on the cement floor beneath a lower shelf at the back. There were eight shelves across the rear wall, divided in the center by a vertical board into two tiers. Bob placed his load on a lower shelf and Laurie put his on the shelf above. As he drew away he noticed that the shelf appeared to have worked out from the boards at the back, and he gave it a blow on the edge with the flat of one hand. It slipped back into place, but, to his surprise, it came forward again an inch or two, and all the other shelves in that tier came with it!

“Hey!” said Laurie, startled.

Bob, at the doorway, turned. “What’s the matter?” he asked.

“Nothing, only—” Laurie took hold of the shelf above the loosened one and pulled. It yielded a little, and so did the other shelves and the rear wall of the cubicle, but it was only a matter of less than an inch. Bob, at his side, looked on interestedly.

“That’s funny,” he said. “Push on it.”

Laurie pushed, and the tier went back a couple of inches. “Looks like this side was separate from the rest,” said Laurie. “What’s the idea of having it come out like that?”

“Search me!” answered Bob. “Pull it toward you again and let me have a look.” A second later he exclaimed: “The whole side is loose, Nod, but it can’t come out because the ends of the shelves strike this partition board! Try it again!” Laurie obeyed, moving the tier back and forth three or four times as far as it would go. Bob shook his head in puzzlement, his gaze roving around the dim interior. Then, “Look here,” he said. “The shelves on the side aren’t on a level with the back ones, Nod.”

“What of it?”

“Nothing, maybe; only, if the back swung out the side shelves wouldn’t stop it! See what I mean?”

“Not exactly. Anyhow, it doesn’t swing out, so what’s the—”

“Hold on!” Bob sprang forward and seized the edge of a shelf in the right-hand tier close to the partition board, and pulled. It readily yielded an inch, but no more.

“Wait!” Laurie bent and pulled aside the box of jars. “Now!”

Then, as Bob tugged, to their amazement the right-hand tier swung toward them, its lower edge scraping on the cement floor, and the left-hand tier swung with it, the whole back wall of the closet, shelves and all, opening toward them like a pair of double doors!

“Gee!” whispered Laurie. “What do you suppose—”

“Pull them wide open and let’s find out,” said Bob recklessly.

When the two sides were open as far as they would go, there was an aperture between them some three feet wide. Beyond it was darkness, though, as they gazed, the stones of the cellar wall took shape dimly. Then Laurie seized Bob’s arm.

“Look!” he whispered excitedly. Behind, where the left-hand tier of shelves had stood, was a blacker patch about three feet high by two feet wide, which, as they stared in fascination, evolved itself into an opening in the wall.

“Know what I think?” asked Bob, in low tones. “I think we’ve found the miser’s hiding-place, Nod!”

“Honest? Maybe it’s just a—a drain or something. Got a match?”

“There are some over by the furnace. Hold your horses!” Bob hurried out, and was back in a moment and was standing at the opening between the doors with a lighted match held toward the opening in the wall. As the little light grew they saw that the stones of the wall had been removed from a space of a foot above the floor and three feet high and some two feet wide. Around the opening so made cement had been applied in the form of a smooth casing.

The match flickered and went out, and in the succeeding gloom the two boys stared at each other with wide eyes.

“Would you dare go in there?” asked Laurie.

“Sure! Why not? It can’t be anything but a sort of cave underground. Wait till I get a candle.”

“A lantern would be better,” suggested Laurie, viewing the hole dubiously.

“That’s so, and there’s one here somewhere. I noticed it the other day.” Bob’s voice came from the cellar beyond, and Laurie heard him walking around out there. Then, “I’ve got it!” Bob called. “There’s oil in it, too! Now we’ll have a look!”

Laurie heard the chimney of the lantern squeak as it was forced up and then drop into place again. Then a wan light came toward the closet, and Bob appeared, triumphant and excited. “Wait till I turn it up a bit. There we are! Come on!”

They passed through between the doors, Bob leading, and stooped before the hole in the wall. Bob held the lantern inside, and Laurie peered over his shoulder. “Gee, it’s high,” whispered the latter.

“Yes, and it isn’t a cave at all; it’s a tunnel!” said Bob, in awed tones. “What do you say?”

“I’ll go, if you will,” replied Laurie, stoutly; and without much enthusiasm Bob ducked his head and crawled through. Past the two-foot wall was a passage, more than head-high and about a yard in width, stone walled and arched, that led straight ahead farther than the light of the lantern penetrated. The walls were dry, but the earthen floor was damp to the touch. There was a musty odor, though the air in there seemed fresh.

“Where do you suppose it goes to?” asked Bob, in a hushed voice.

“I can’t imagine. But it runs straight back from the cellar, and so it must pass under the garden. Let’s—let’s go on, Bob.”

“Sure! Only I thought we were going to find old Coventry’s treasure!”

“How do you know we aren’t?” asked Laurie.

“That’s so! Maybe he buried it under the garden.” Their footfalls sounded clearly on the hard-packed earth floor as they went ahead. Suddenly Bob, in the lead, uttered an exclamation, and Laurie jumped a foot and then hurried forward to where the other was standing. Beside him, its point buried in the floor of the tunnel, was the lost crowbar!

“What do you know?” gasped Bob. “We’re under the farther end of the arbor. That bar came through between those stones up here.” He touch the crevice in the arched roof with a finger. “See the dirt it brought down with it? Well, that explains that mystery!”

“Yes, but—where does this thing go to, Bob?”

“Let’s find out. It can’t go much farther, because the arbor was only about forty feet from the back fence.”

But they went that forty feet and perhaps forty more before the wavering light of the lantern showed them a stout wooden door across their path. Formed of two-inch planking and strengthened with three broad cleats, it was hinged to a frame of concrete. It wasn’t a big door, but it looked very formidable to the two boys who stood there and viewed it dubiously in the yellow glare of the lantern; for a big square iron lock held it firmly in place.

“Guess we don’t go any farther,” said Bob, dryly.

“Maybe the key’s here somewhere,” Laurie suggested; and, although Bob scoffed at the suggestion, they searched thoroughly but without success.

“We could bust it,” Bob said; “only maybe we haven’t any right to.”

“I don’t see why not, Bob. We discovered it. Let’s!”

“We-ell, but one of us’ll have to go for a hammer or something.”

“Sure; I’ll go.”

“And leave me here in the dark? I guess not!”

“We’ll both go, then. Hold on! What’s the matter with the crowbar?”

“Of course! I never thought of that! I’ll fetch it!” The light receded down the tunnel until it was small and dim, and Laurie, left alone in front of the mysterious portal, felt none too happy. Of course there was nothing to be afraid of, but he was awfully glad when the light drew nearer again and Bob returned. “You hold this,” directed Bob, “and I’ll give it a couple of whacks.”

Laurie took the lantern, and Bob brought the bar down smartly on the lock. Probably it was old and rusty, for it broke into pieces under the blow, and in another instant they had thrust the heavy bolt back. Then Bob took a long breath and pulled the door toward them. The hinges squeaked loudly, startlingly, in the silence. Before them lay darkness, and Laurie, leaning past the doorway, raised the lantern high.